The present invention relates to a starter protection circuit for the starting device of an internal combustion engine of a vehicle, particularly a motor vehicle.
The internal combustion engines of vehicles, particularly of passenger-carrying motor vehicles and utility vehicles are equipped with an electrically operating starting device. Via a start switch to be operated by means of an ignition key, a starter relay can be operated which connects a starter to a battery of the vehicle and establishes a mechanical coupling between starter and internal combustion engine via a pinion arrangement. As soon as the internal combustion engine has started, the driver of the vehicle opens the start switch by releasing the ignition key as a result of which the starter relay drops out and the starter is taken out of operation. The starter is only suitable for a short-time operation, that is to say it can only withstand a warming caused by the relatively large starter current for the short time of a starting process. Thus, a starter failure (in most cases total loss due to overheating) will occur if, for example, the start switch "hangs up" since this leads to a continuous operation of the starter for which it is not designed.